Fluid sensing cutter control

ABSTRACT

A pneumatic control device suitable for activating a shear and for attachment to a sewing machine employs two sensing air jets in a shoe and block combination, the shoe and block being spaced apart for the reception of work material. The distances between the sensing jets and the shear are separately adjustable, either continuously or step-wise. A shuttle valve and pulse generators are so arranged that interruption of the first jet by work material causes a first cutting stroke of the shear and essentially immediate retraction of the shear to a rest position, and so that restoration of the second sensing jet resulting from removal of the work material causes a similar second cutting stroke.

United States Patent Hoffee FLUID SENSING CUTTER CONTROL Joseph M.Hoffee, 725 Sixth Avenue, New York, NY. 10009 Filed: April 1, 1971 Appl.No.: 130,137

Inventor:

References Cited UNITED STATES PATENTS 4/1968 Pitney ..73/37 2/1969Miller et al. ..112/130 7/1971 Martinez ..l37/81.5 1/1972 Conner ..l12/DIG. 2

DETECmR RECE/VER REgg/VER 1 Oct. 24, 1972 5 7 ABSTRACT A pneumaticcontrol device suitable for activating a shear and for attachment to asewing machine employs two sensing air jets in a shoe and blockcombination, the shoe and block being spaced apart for the reception ofwork material. The distances between the sensing jets and the shear areseparately adjustable, either continuously or step-wise. A shuttle valveand pulse generators are so arranged that interruption of the first jetby work material causes a first cutting stroke of the shear andessentially immediate retraction of the shear to a rest position, and sothat restoration of the second sensing jet resulting from removal of thework material causes a similar second cutting stroke.

10 Claims, 9 Drawing Figures WORK PIECE A KEGUMTUI? ENSDR E} JsruzSENSOR JET! REGULATOR v 40 AMPL lF/ER VAL YES BELLOWS ACTUATED PULSEG'E/i/[RflN/PS Sill/7726' VALVE P/LOI' VALVE 59 AIR CYLINDER 72) 467-04TE sc/ssafis PATENTED CT 24 1972 sum 1 [IF 6 INVESTOR. JOSEPH M. HOFFEEPATENTED i973 3.699.908

sum 2 OF 6 30 V P-4 m IXVENTOR. JOSEPH M. HOFFEE PATENTEDncr 24 I972SHEET 3 OF 6 INVENTOR. JOSEPH M. HOFFEE SHEEI 5 0F 6 PATENTED 0m 24-I972 INVENTOR. JOSEPH M. HOFFEE ATTORNEYS PATENTED H 24 3 699.908

SHEEI s or 6 DETEC7DR RECEIVER RECEIVER JET 1 #2 WORK PIECE A 1P66001701? SEA/50R AIR 0 I JET#2 40 SENSOR JET 1 REGULATOR l i r 0 I l l47 40 AMPLIFIER VAL VES l BEAAOWS 4670A TED.

l A. I 4/ L L J PULSE G'E/VfRflTO/PS Sm/7745 v44 1 5 1 /407 VALVE 39 AIRc Y1. INDER INVENTOR. JOSEPH M. HOFFEE ATTORNEYS FLUID SENSING CUTTERCONTROL BACKGROUND OF THE INVENTION This invention is concerned with aclass of applications wherein the arrival of a workpiece or workmaterial at a machine is to cause the machine to take a specific action,and wherein the removal of the piece from the machine is to cause themachine to take a second specific action. The two specific actions mayor may not be the same. Moreover, two sensors must be provided since thepoints at which the workpiece or work material arrives at the machineand departs from the machine may be different. An example of such amachine is a sewing machine to which may be brought a piece of materialor a garment to the edge of which is to be sewn a binding. In such acase, the sensors are used to activate a shear which cuts the binding toa desired length. Two cuts per garment are needed since the position ofeach end of the binding with respect to the garment must be controlled.

Conventionally, electric eyes in pairs have been used for the abovepurpose. However, considerable vibration and shock are involved in theoperations described, and it has been found that the reliability and thelife of such optically controlled systems are inadequate. Moreover, inthe attempt to increase the life and reliability of optical systems inthe associated electronics systems, the introduction of sturdiercomponents increases the bulk and weight of the control system to thepoint where it can no longer be used in combination with relativelysmall devices such as sewing machines.

SUMMARY OF THE INVENTION Pneumatic control systems are known to offerboth long life and high reliability, in combination with compact size.Furthermore, highly reliable components of a relatively high degree ofsophistication have become available at low cost as the result of thedevelopment of the science of fluidics. Such components have been foundto serve the present purpose admirably.

The present invention may be exemplified in its use in combination witha sewing machine. More specifically, the invention is used to activate ashear when a garment is brought to the machine and to activate the shearfor a second stroke when the garment is removed from the machine. Theportion of the device which initiates the first cutting stroke comprisesa first sensor jet and a detector jet. Both jets are located in the sameplane and are related in the same sense as the stem and the cross bar ofa T. In the absence of the sensor jet the detector jet would enter areceiver hole, but normally, the sensor jet intersects with andinterferes with the detector jet so that air from the detector jet doesnot enter the receiver hole. However, introduction of a garment into thesensor jet abruptly interrupts the flow of the sensor jet and permitsthe detector jet to enter the receiver hole causing a sudden rise inpressure therein. This rise in pressure is transmitted through a pulsegenerator to a shuttle valve which activates the shear for a singlestroke and return.

The device further comprises a second sensor jet and a second receivinghole. Introduction of the work material into the second sensor jetduring the traverse of the sewing machine by the work material has noeffect on the shear, since such an interruption causes a drop inpressure in the receiving hole and the device is designed so that itresponds only to an increase in pressure. However, when the garment isremoved from the second sensor jet, the sudden rise of pressure in thereceiving hole then activates the shear.

It is an important feature of the present invention that the distancefrom each of the sensor jets to the shear can be individually adjusted.The adjustment over a suitable range may be either stepwise orcontinuous.

Accordingly it is an object of the present invention to provide apneumatic device of high reliability and long like for the activation ofequipment.

Another object of the invention is to provide such a device whichactivates equipment both on introduction of work material and on removalof work material.

A further object of the invention is to provide a pneumatic activationdevice having two stations, in which the distance from each station tothe equipment to be activated is separately adjustable, eithercontinuously or stepwise.

Still another object of the invention is to provide an improvedpneumatic device for activation of equipment which is low in cost.

Still other objects and advantages of the invention will in part beobvious and will in part be apparent from the specification.

The invention accordingly comprises the features of construction,combination of elements, and arrangement of parts which will beexemplified in the construction hereinafter set forth, and the scope ofthe invention will be indicated in the claims.

BRIEF DESCRIPTION OF THE DRAWINGS For a fuller understanding of theinvention, reference is had to the following description taken inconnection with the accompanying drawings, in which:

FIG. 1 is a schematic perspective representation of a sewing machinehaving a device in accordance with the present invention mountedthereon;

FIG. 2 is a partial elevational view of the device in which theequipment to be activated is a shear;

FIG. 3 is a partial sectional view taken along line 3- 3 of FIG. 2;

FIG. 4 is a partial sectional view taken along line 4 4 of FIG. 3;

FIG. 5 is a partial sectional view taken along line 5- 5 of FIG. 2;

FIG. 6 is a partial sectional view taken along line 6- 6 of FIG. 2;

FIG. 7 is a partial sectional view taken along line 7- 7 of FIG. 2;

FIG. 8 is a perspective view of a segmented shoe and block; and

FIG. 9 is a schematic diagram showing the system of air connections.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, the deviceof the present invention generally designated as 1, is mounted incombination with a sewing machine 5. A block 3 is supported over theshoe 2. The work 4, in this case a garment to which an edge binding isto be applied is moved between the block 3 and the shoe 2 in thedirection shown for the application of edge binding. In FIG. 2 themovable knife 6 combines with the fixed knife 7 to form a shear. Themovable knife 6 rotates around the knife pivot 8; the block 3 issuspended by means of the bracket 9. Low pressure air is brought to thejets by means of the low pressure air supply hose 10. The pivot end ofthe high pressure cylinder 43 that operates the shear is shown at 11. Abellows valve which amplifies the pressure rise resulting fromintroduction of a jet into a receiver hole is shown at 12. The pulsegenerator 13 receives the output from the bellows valve and generates asingle pulse which activates a shuttle valve 37 (FIG. 9) and, in turn,the shear.

Referring to FIGS. 3 through 6, a first sensor hole 14 emits a verticalsensor jet which passes in front of the detector hole 17 which isemitting a horizontal detector jet toward the receiving hole 19 in whichis mounted the hose leading to the amplifier valve. An additional sensorhole 15 and an additional detector hole 18 are both blocked by pieces oftape 16. The air supply to both detector holes 17 and 18 is introducedthrough the hose 26 and the detector manifold 27. The sensor holes 14and 15, the detector holes 17 and 18, and the receiver holes 19 and 21make up the first station. The sensor hole 22, the additional sensorholes 23, which are blocked by the tape 16, the receiver hole 24 inwhich is mounted the hose 29 going to the amplifier valve, and theadditional receiver holes 25 make up the second station. Normally, thesensor jet emanating from the first sensor hole 14 interrupts thedetector jet emanating from the detector hole 17 so that the receiverhole 19 is essentially at atmospheric pressure. Introduction of agarment or other work material to interrupt the first sensor jet,results in the detector jet from hole 17 reaching the receiver hole 19and causing a small pressure rise therein. This rise in pressure istaken through the hose 20 to a bellows amplifier, thence to a pulsegenerator and a shuttle valve and finally to a hydraulic cylinder whichpowers the shear through a cutting cycle and return to the restposition.

Advancement of the garment between the shoe and the block to the pointwhere it interrupts the second sensor jet emanating from the hole 22does not activate the shear since the system is sensitive only to anincrease in pressure. However, when the garment is removed from abovethe hole 22, the jet once more enters the receiving hole 24 causing anincrease in pressure which as before leads to a stroke of the shear.

To change the position of the first station and thereby the distancebetween the activation point and the shear, it is only necessary totransfer the tape 16 from the hole 15 to the hole 14 and from the hole18 to the hole 17 and to transfer the tube 20 from the hole 19 to hole21. A similar change in the position of the tape 16 at one of the holes23 and a change in the location of the tube 29 in the receiving holemakes it possible to change the location of the second activating point.The changes in the first and second activation points can be carried outindependently, of course, and, as is evident, the changes are made insteps.

FIG. 5 shows the means by which the low pressure air reaches the sensorholes of the first and second stations from the hoses 30 and 31.

Referring now to FIG. 7, the location of the sensor hole 14, thedetector hole 17, the receiver hole 19 and the hose 20 leading to anamplifier valve are shown. This view also shows the binding 32 which isto be applied to the garment.

FIG. 8 is a perspective view of the block and shoe so constructed as tomake continuous adjustment of the various distance involved feasible.The shoe 2 consists of two segments 20 and 2b which are slidable withrespect to each other as a result of the tongue and groove connection33. Similarly the block is also constructed in two segments 3a and 3bagain joined by a tongue and groove arrangement. Segments 2a and 3acomprise the first station and segments 2b and 3b comprise the secondstation. In FIG. 8 the two parts of the second station are mountedrigidly with respect to each other by means of the bracket 34. Thebracket 34 is held to the base 42 by the screws 36 in the slot 35. Thisarrangement makes it possible to shift the position of the secondstation without losing the alignment between the second sensing jet andthe second receiver hole. A similar bracket, not shown, can be used tohold the segments of the first station in alignment.

FIG. 9 is a schematic diagram showing the pneumatic components andconnections. Low pressure air is provided by the regulators 40 to sensorjets 1 and 2 and to the detector jet. Normally the sensor jet No. lintersects the detector jet so that no impulse is received in thereceiver hole of the first station. Interruption of the first sensor jetby the work material restores the detector jet which is received in thereceiving hole; the resultant pressure rise is transmitted to theamplifier valve 41 and thence to the pulse generator 13, in turn to theshuttle valve 35 and finally to the pilot valve 38 which supplies highpressure air to the air cyclinder 39 which actuates the shear 6. Whenthe work material is removed from the second sensor jet, the jet entersthe receiver hole of the second station and the transmitted pressurerise traverses a second path similar to that described above, to actuatethe air cyclinder and the shear.

It will thus be seen that the objects set forth above, among those madeapparent from the preceding description, are efficiently attained and,since certain changes may be made in the above construction withoutdeparting from the spirit and scope of the invention, it is intendedthat all matter contained in the above description or shown in theaccompanying drawings shall be interpreted as illustrative and not in alimiting sense.

It is also to be understood that the following claims are intended tocover all of the generic and specific fea tures of the invention hereindescribed, and all statements of the scope of the invention which, as amatter of language, might be said to fall therebetween.

What is claimed is:

1. Compact, adjustable, two-station pneumatic activation device,comprising a first sensing jet, a detector jet spaced from said firstsensing jet and located perpendicular to and in the same plane as saidfirst sensing jet so that said first sensing jet normally intersectssaid detector jet, a first receiver hole aligned to receive saiddetector jet, a first pulse generator connected to said first receiverhole and pneumatically connectable to equipment to be activated in asingle operation cycle, a second sensing jet spaced apart from saidfirst sensing jet, a second receiving hole aligned to receive saidsecond sensing jet, and a second pulse generator, connected to saidsecond receiver hole and pneumatically connectable to saidequipment-to-be-activated in a single operation cycle, said pulsegenerators functioning in response to an increase in pressure in saidrespective receiver holes, whereby interruption of said first sensingjet by the introduction of work material between said sensing anddetector jets causes operation of said equipment-to-be-activated, andrestoration of said second sensing jet subsequent to interruption bywork material causes operation of said equipment-tobe-activated.

2. Compact, adjustable, two-station, pneumatic, control device,comprising a shoe member having a longitudinal axis and a block memberhaving a matching, parallel longitudinal axis, said block member beingsupported in registry with and spaced apart from said shoe member thusproviding room therebetween for the introduction of work material, saidshoe and block members each having a first and a second station spacedalong said axes, said shoe member having at said first station a firstsensor hole directed toward said block member, and connectable to asource of low pressure air to form a first sensing jet emanating fromsaid first sensor hole, said block member in the region of said firststation being generally U-shaped, with the opening of said U directedtoward said shoe member, one leg of said U at said first station havinga detector hole therein directed perpendicular to and in the same planeas said first sensor hole and being connectable to a source of lowpressure air to form a detector jet emanating from said detector holetoward the other leg of said U, said other leg of said U having thereina first receiver hole aligned with said detector hole and beingpneumatically connectable with equipment to be activated, one of saidmembers at said second station having therein a second sensor holedirected toward the other of said members and connectable to a source oflow pressure air to form a second sensing jet emanating from said secondsensor hole, the other of said members having therein at said secondstation a second receiving hole aligned with said second sensor hole andbeing pneumatically connectable with said equipment-to-be-activated, andmeans for independently varying the distance between said first stationsand said equipmentto-be-activated, and the distance between saidsecondstations and said equipment-to-be-activated.

3. Control device as defined in claim 2 wherein said shoe member andsaid block member are divided into a shoe first station segment, a shoesecond station segment, a block first station segment and a block secondstation segment, said shoe first station segment and said block firststation segment being mounted rigidly together, said shoe second stationsegment and said block second station segment being mounted rigidlytogether, said shoe first and second station segments being mountedslidably along said longitudinal axis with respect to said equipment tobe controlled and said block first and second station segments beingmounted slidably along said longitudinal axis with respect to saidequipment to be controlled.

4. Control device as defined in claim 2 wherein said first shoe stationhas at least one additional first sensor hole spaced apart from saidfirst sensor hole, along said [on 'tudinal axis, and parallel to saidfirst sensor hole, sai additional first sensor hole being connectable toa source of low pressure air, means being provided for selecting asingle first sensor hole through which the first sensor jet emanates,and wherein said first block station has at least one additionaldetector hole and at least one additional receiver hole spaced apartfrom said first detector and receiver holes by an amount and in adirection corresponding to the additional first sensor hole and beingcorrespondingly connectable to a source of low pressure air and theequipment to be controlled, thereby achieving stepwise adjustment of thedistance between the first station and the equipment to be controlled.

5. Control device as defined in claim 2 wherein said one of said membersat said second station has therein at least one additional second sensorhole spaced apart from said second sensor hole along said axis andparallel to said second sensor hole, said additional second sensor holebeing connectable to a source of low pressure air, means being providedfor selecting a single second sensor hole through which said secondsensor jet emanates, and wherein said other of said members at saidsecond station has therein at least one additional receiver hole spacedapart from said second receiver hole by an amount and in a directioncorresponding to said additional second sensor hole and beingcorrespondingly connectable to said equipment to be activated, therebyachieving stepwise adjustment of the distance between the second stationand the equipment to be activated.

6. Control device as defined in claim 1 wherein said equipment to beactivated is a shear.

7. Control device as defined in claim 6 wherein said shear is mounted onand cooperates with a sewing machine.

8. Control device as defined in claim 6 wherein said shear, in responseto the passage of said work material through said sensing jets cuts to adesired length a binding material applied to said work material.

9. Control device as defined in claim 5 further comprising a shuttlevalve so arranged as to cause a single stroke and essentially immediate,subsequent retraction of said equipment-to-be-activated to a restposition as each pulse from said pulse generators is received.

10. Control device as defined in claim 2 wherein said one member is asaid shoe member and said other member is said block member.

1. Compact, adjustable, two-station pneumatic activation device,comprising a first sensing jet, a detector jet spaced from said firstsensing jet and located perpendicular to and in the same plane as saidfirst sensing jet so that said first sensing jet normally intersectssaid detector jet, a first receiver hole aligned to receive saiddetector jet, a first pulse generator connected to said first receiverhole and pneumatically connectable to equipment to be activated in asingle operation cycle, a second sensing jet spaced apart from saidfirst sensing jet, a second receiving hole aligned to receive saidsecond sensing jet, and a second pulse generator, connected to saidsecond receiver hole and pneumatically connectable to saidequipment-to-be-activated in a single operation cycle, said pulsegenerators functioning in response to an increase in pressure in saidrespective receiver holes, whereby interruption of said first sensingjet by the introduction of work material between said sensing anddetector jets causes operation of said equipment-to-be-activated, andrestoration of said second sensing jet subsequent to interruption bywork material causes operation of said equipment-to-be-activated. 2.Compact, adjustable, two-station, pneumatic, control device, comprisinga shoe member having a longitudinal axis and a block member having amatching, parallel longitudinal axis, said block member being supportedin registry with and spaced apart from said shoe member thus providingroom therebetween for the introduction of work material, said shoe andblock members each having a first and a second station spaced along saidaxes, said shoe member having at said first station a first sensor holedirected toward said block member, and connectable to a source of lowpressure air to form a first sensing jet emanating from said firstsensor hole, said block member in the region of said first station beinggenerally U-shaped, with the opening of said U directed toward said shoemember, one leg of said U at said first station having a detector holetherein directed perpendicular to and in the same plane as said firstsensor hole and being connectable to a source of low pressure air toform a detector jet emanating from said detEctor hole toward the otherleg of said U, said other leg of said U having therein a first receiverhole aligned with said detector hole and being pneumatically connectablewith equipment to be activated, one of said members at said secondstation having therein a second sensor hole directed toward the other ofsaid members and connectable to a source of low pressure air to form asecond sensing jet emanating from said second sensor hole, the other ofsaid members having therein at said second station a second receivinghole aligned with said second sensor hole and being pneumaticallyconnectable with said equipment-to-be-activated, and means forindependently varying the distance between said first stations and saidequipment-to-be-activated, and the distance between said second stationsand said equipment-to-be-activated.
 3. Control device as defined inclaim 2 wherein said shoe member and said block member are divided intoa shoe first station segment, a shoe second station segment, a blockfirst station segment and a block second station segment, said shoefirst station segment and said block first station segment being mountedrigidly together, said shoe second station segment and said block secondstation segment being mounted rigidly together, said shoe first andsecond station segments being mounted slidably along said longitudinalaxis with respect to said equipment to be controlled and said blockfirst and second station segments being mounted slidably along saidlongitudinal axis with respect to said equipment to be controlled. 4.Control device as defined in claim 2 wherein said first shoe station hasat least one additional first sensor hole spaced apart from said firstsensor hole, along said longitudinal axis, and parallel to said firstsensor hole, said additional first sensor hole being connectable to asource of low pressure air, means being provided for selecting a singlefirst sensor hole through which the first sensor jet emanates, andwherein said first block station has at least one additional detectorhole and at least one additional receiver hole spaced apart from saidfirst detector and receiver holes by an amount and in a directioncorresponding to the additional first sensor hole and beingcorrespondingly connectable to a source of low pressure air and theequipment to be controlled, thereby achieving stepwise adjustment of thedistance between the first station and the equipment to be controlled.5. Control device as defined in claim 2 wherein said one of said membersat said second station has therein at least one additional second sensorhole spaced apart from said second sensor hole along said axis andparallel to said second sensor hole, said additional second sensor holebeing connectable to a source of low pressure air, means being providedfor selecting a single second sensor hole through which said secondsensor jet emanates, and wherein said other of said members at saidsecond station has therein at least one additional receiver hole spacedapart from said second receiver hole by an amount and in a directioncorresponding to said additional second sensor hole and beingcorrespondingly connectable to said equipment to be activated, therebyachieving stepwise adjustment of the distance between the second stationand the equipment to be activated.
 6. Control device as defined in claim1 wherein said equipment to be activated is a shear.
 7. Control deviceas defined in claim 6 wherein said shear is mounted on and cooperateswith a sewing machine.
 8. Control device as defined in claim 6 whereinsaid shear, in response to the passage of said work material throughsaid sensing jets cuts to a desired length a binding material applied tosaid work material.
 9. Control device as defined in claim 5 furthercomprising a shuttle valve so arranged as to cause a single stroke andessentially immediate, subsequent retraction of saidequipment-to-be-activated to a rest position as each pulse from saidpulse generators is received.
 10. Control device as defined in claim 2wherein said one member is a said shoe member and said other member issaid block member.